Few individuals in need of substance abuse services actually receive them. Estimates suggest that in the United States, only 10% of individuals with substance abuse disorders ever obtain services for their condition. Among the most commonly cited barriers to access among seekers of substance abuse services is wait time. Empirical studies corroborate this claim, suggesting that waiting more than a single day decreases the likelihood that an individual seeking services will show up when they become available. Despite the critical importance of wait time as a component of access, no studies have attempted to document-at least not at the state or national level-how long individuals typically wait to receive substance abuse services in the publicly- funded system. Additionally, it is unknown whether there are gender differences in wait time. While at least three studies suggest that women may wait longer than men to receive substance abuse services after initial request, these studies suffer from significant methodological weaknesses, including limited generalizability, non-representative sampling, and the absence of measures to address censoring. Similarly, little is known about the factors that drive wait time to receive services. To address this gap, this study will identify components of substance abuse service policy, financing and programs that are associated with shorter wait time to treatment entry for men and women. Additionally, it will identify client populations that are most likely to experience long wait times to enter treatment and thus may be particularly vulnerable to pre-treatment dropout. Such knowledge can be used to inform the development of targeted interventions at the levels of policy and practice to reduce wait times. To this end, the study will develop multilevel proportional hazard models to pursue the following specific aims: (1) to examine how the likelihood of assessment changes as a function of wait time by gender; (2) to identify client and program factors associated with wait time to assessment by gender; (3) to examine how the likelihood of treatment entry changes as a function of wait time by gender; and (4) to identify client and program factors associated with wait time to treatment entry by gender. To conduct the study, data from the Illinois Division of Alcoholism and Substance Abuse (DASA) will be used. The study will include roughly 200,000 treatment records from 2006- 2008 from the DASA Automated Reporting and Tracking System (DARTS). DARTS includes unique client identifiers that allow for tracking clients' movements throughout the system. While this dataset is not publicly available, permission to use it has already been secured. PUBLIC HEALTH RELEVANCE: Despite the significant economic, social, and public health costs of substance abuse, as few as 10% of individuals with substance use disorders ever receive services for their condition. Among the most commonly-cited reasons for not entering treatment is wait time to receive services. The proposed study will identify specific factors at the levels of policy and practice that can be reworked to decrease wait times and consequently improve rates of substance abuse treatment access in the public system.